Global map of HIV reveals challenge to vaccine development

A study to be published in The Lancet Infectious Diseases on World AIDS Day shows the extraordinary global genetic diversity of HIV and highlights just how big the challenge is to develop a vaccine to combat the global spread of HIV. One of the most comprehensive studies of HIV around the world has revealed a map of the spread of subtypes of the virus across the world, revealing which strains are dominant in which country and region, and where new strains are emerging. The systematic review and global survey, led by Dr Joris Hemelaar of the University of Oxford, analysed 383,519 samples from 116 countries spanning the period 1990-2015. It found that the greatest diversity of HIV was found in Central Africa, but it also showed that different variants of HIV prevail in different regions of the world. What is more, the distribution of HIV strains is evolving over time and recombinants are increasing and now account for nearly a quarter (22·8%) of all global HIV infections. The analysis showed that so-called 'subtype C' causes the greatest number of global HIV infections (46.6%) and that subtype C is the near-exclusive strain of HIV in southern Africa, where HIV prevalence is highest. This data therefore strengthens the case for the prioritisation of the development of a subtype C-specific HIV vaccine for this region.